临床儿科杂志 ›› 2014, Vol. 32 ›› Issue (5): 471-475.

• 实验研究 • 上一篇    下一篇

维生素D对高糖诱导足细胞胰岛素抵抗的保护作用

邹敏书1, 余健1, 聂国明1, 罗莉漫1, 徐洪涛1, 尹晓玲2, 周建华2   

  1. 1. 广州军区武汉总医院儿科(湖北武汉 430070);2. 华中科技大学同济医学院同济医院儿科(湖北武汉 430030)
  • 收稿日期:2013-12-07 出版日期:2014-05-15 发布日期:2014-05-15

Protective effect of vitamin D on high glucose-induced podocyte insulin resistance    

ZOU Minshu1, YU Jian1, NIE Guoming1, LUO Liman1, XU Hongtao1, YIN Xiaoling2, ZHOU Jianhua2   

  1.  (1. Department of pediatrics, Wuhan General Hospital of Guangzhou Command of PLA, Wuhan 430070,China; 2. Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China)
  • Received:2013-12-07 Online:2014-05-15 Published:2014-05-15

摘要:

足细胞+5mmol/L葡萄糖(A组),足细胞+5mmol/L葡萄糖+1nmol/L丙二醇(B组),足细胞+30mmol/L葡萄糖+1nmol/L丙二醇(C组),足细胞+30mmol/L葡萄糖+1nmol/L丙二醇+1nmol/L VitD(D组)。培养48 h测定足细胞凋亡百分率,MTT法测定足细胞活性,RT-PCR测定足细胞维生素D受体(VDR)及胰岛素受体底物蛋白1(IRS1)的表达,Western blotting检测IRS1、肌醇依赖蛋白激酶(Akt)、细胞外调节蛋白激酶(ERK1/2)的表达及其磷酸化水平。结果 四组间足细胞凋亡及活力,VDR和IRS1基因表达水平,信号蛋白IRS1、ERK1/2磷酸化水平的差异均有统计学意义(P均<0.05),Akt磷酸化水平的组间差异无统计学意义(P>0.05)。与A、B和D组相比,C组足细胞凋亡百分率升高,足细胞活力降低,VDR和IRS1 mRNA表达下调,IRS1磷酸化水平下降,ERK1/2磷酸化水平升高,差异均有统计学意义(P均<0.05);而A、B、D三组间p-IRS1/IRS1、p-ERK1/2/ ERK1/2水平差异均无统计学意义(P>0.05)。结论 VitD-VDR系统减轻高糖诱导的足细胞凋亡,活化胰岛素信号通路,拮抗胰岛素抵抗信号,改善足细胞胰岛素抵抗。

Abstract:  Objective To study the protective effects of vitamin D (VitD) on podocyte insulin resistance and its mechanisms. Methods Immortalized mouse podocytes in vitro were randomly divided into 4 groups: podocytes+5mmol/L glucose group (group A); podocytes+5mmol/L glucose+1nmol/L propylene glycol group (group B); podocytes+30mmol/L glucose+1nmol/L propylene glycol group (group C); podocytes+30mmol/L glucose+1nmol/L propylene glycol+1nmol/L VitD group (group D). The percentage of podocyte apoptosis was determined after 48 h of incubation. Podocyte viability was assessed by MTT assay. The mRNA expressions of vitamin D receptor (VDR) and insulin receptor substrate protein 1 (IRS1) in podocyte were detected by RT-PCR. Western blot analysis was performed to measure the protein levels of p-IRS1/IRS, p-Akt/Akt and p-ERK1/2/ERK1/2. Results There were significant differences in apoptosis percentage, viability and the expression of VDR, IRS1, p-ERK1/2 of podoctyes(P<0.05)among 4 groups. There was no difference in p-Akt/Akt expression among 4 groups(P>0.05). Compared with group A, B , and D, the percentage of podocyte apoptosis in group C was significantly increased, the cell viability was decreased, the expressions of VDR and IRS1 mRNA and p-IRS1 and p-Akt proteins were down-regulated, whereas p-ERK1/2 was up-regulated in group C. The levels of p-IRS1/IRS1, p-Akt/Akt, p-ERK1/2 / ERK1/2 had no statistical differences in group A, B, and D (P>0.05). Conclusions VitD-VDR system alleviates podocyte apoptosis induced by high glucose, and activates insulin signaling pathway and counteracts insulin resistance signal to improve podocyte insulin resistance.